“Eighty percent of what they eat is vegetables and whole grains: brown rice, quinoa, millet, beans,” Campbell told Boston.com. “The other 20 percent is lean meats: grass-fed organic steak, duck every now and then, and chicken. As for fish, I mostly cook wild salmon.”

However, there are certain vegetables Brady, 38, won’t eat at all.

“[Tom] doesn’t eat nightshades, because they’re not anti-inflammatory,” explains Campbell. “So no tomatoes, peppers, mushrooms, or eggplants. Tomatoes trickle in every now and then, but just maybe once a month.”

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“It’s very different than a traditional American diet, but if you just eat sugar and carbs – which a lot of people do – your body is so acidic, and that causes disease,” Campbell told the website. “Sugar is the death of people.”

Despite their strict diet most days of the year, Brady recently told PEOPLE that biscuits are a holiday staple in their house.

“My grandma always had a biscuit recipe that she used to make for us, so every holiday – Thanksgiving, Easter, Christmas – there is biscuit making,” he said. “That s a little bit of tradition in our house now.”